/*
    This file is part of the substandard lisp implementation of Standard Lisp
    Copyright (C) 2011 Nicky Nickell

    substandard lisp is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

(de pnth (i l)
  (cond ((eqn i 0) l)
        (t (pnth (sub1 i) (cdr l)))))

/*---
name: pnth

synonyms:
  - nthcdr

doc: |
  returns the zero indexed I'th cdr of L

tests: |
  (setq a '(1 2 3 4 5 6 7))
  (pnth 0 a) -> (1 2 3 4 5 6 7)
  (pnth 1 a) -> (2 3 4 5 6 7)
  (pnth 2 a) -> (3 4 5 6 7)
...*/
